W+K

So the main difference is the considerably larger size of W+K Portland. And compared to the starkness of Amsterdam's new building, the Portland office has lots of visual stimulation wherever you go. 

The studio is spread out over a whole 'quad' of the 4th floor with people divided by client into small groups with a Studio Manager. Nike seems to take up a lot of people and remains very much the main client. The large entrance area doubles up as a gallery, currently showing an exhibition of 'work that deeply affected you' selected by W+K employees.

Portland

Portland is crazy about recycling. Even if their president doesn't give a rat's ass about the environment, Portlanders do. It's a very liberal, forward thinking city, (toilet signs in braille) has a good public transport system (though not as regular as Amsterdam's) is super friendly and outdoorsy. 

It has a good music scene. It also has more strip clubs per capita than any other American city. Imagine Amsterdam if it was full of Americans, had massive supermarkets and really good customer service (scrap that, had customer service). Mind you, I'm looking forward to being able to buy an alcoholic drink without having to show I.D, and tipping the waiter every time...